Buggy code:
public class StringListWithContentProposalsPropertyController extends PropertyController < String , Object > { private static final StringTokenizerListConverter STRING_TO_LIST_CONVERTER = new StringTokenizerListConverter ( "<seq2seq4repair_space>" , true ) ; private final String [ ] proposals ; private final String tooltip ; private final String defaultValue ; private final IValueEditor < String > valueEditor ; private ILabelProvider labelProvider ; public StringListWithContentProposalsPropertyController ( String id , String displayName , String [ ] proposals , String defaultValue , String tooltip , IValueEditor < String > valueEditor ) { } @ Override protected IPropertyConverter < String , Object > createConverter ( ) { } @ Override public ILabelProvider getLabelProvider ( ) { } @ Override public CellEditor createPropertyEditor ( Composite parent ) { } private static String getWordAt ( String txt , int pos ) { } protected static class ListPropertySource extends ComplexPropertySource < List < String > > { private static final String REMOVE_VALUE = "<removed>&*^&^%&$#@^%$&%%^#$*$($l" ; private final IValueEditor < String > valueEditor ; public ListPropertySource ( ComplexProperty < List < String > > complexProperty , IValueEditor < String > valueEditor ) { } @ Override public IPropertyDescriptor [ ] createPropertyDescriptors ( ) { } @ Override public Object getPropertyValue ( Object id ) { } @ Override protected List < String > setComplexPropertyValue ( Object id , Object value ) { } } public static StringListWithContentProposalsPropertyController . ModifiedContentProposalAdapter createContentProposalAdapter ( Text text , String [ ] proposals , final String tooltip ) { } public static class ModifiedContentProposalAdapter extends ContentProposalAdapter { public ModifiedContentProposalAdapter ( Control control , IControlContentAdapter controlContentAdapter , IContentProposalProvider proposalProvider , KeyStroke keyStroke , char [ ] autoActivationCharacters ) { } @ Override public void openProposalPopup ( ) { } } public static class ReplaceWordsTextContentAdapter extends TextContentAdapter { @ Override public void setControlContents ( Control control , String text , int cursorPosition ) { } private String replaceCurrentWord ( String text , int pos , String replacement ) { } } static abstract class AbstractWordsWithContentProposalCellEditor extends CellEditor { private final String [ ] proposals ; private final String tooltip ; protected Button button ; protected Text text ; private StringListWithContentProposalsPropertyController . ModifiedContentProposalAdapter contentProposalAdapter ; public AbstractWordsWithContentProposalCellEditor ( Composite parent , String [ ] proposals , String tooltip ) { } public StringListWithContentProposalsPropertyController . ModifiedContentProposalAdapter getContentProposalAdapter ( ) { } @ Override public void activate ( ) { } @ Override protected Control createControl ( Composite parent ) { Composite composite = new Composite ( parent , SWT . NONE ) ; text = new Text ( composite , SWT . BORDER ) ; addListeners ( ) ; text . addSelectionListener ( new SelectionAdapter ( ) { @ Override public void widgetDefaultSelected ( SelectionEvent e ) { fireApplyEditorValue ( ) ; deactivate ( ) ; } } ) ; addButton ( composite ) ; GroupLayout groupLayout = new GroupLayout ( composite ) ; SequentialGroup sequentialGroup = groupLayout . createSequentialGroup ( ) ; sequentialGroup . add ( text , PREFERRED_SIZE , 135 , Integer . MAX_VALUE ) ; sequentialGroup . addPreferredGap ( RELATED ) . add ( button ) ; groupLayout . setHorizontalGroup ( sequentialGroup ) ; ParallelGroup parallelGroup = groupLayout . createParallelGroup ( CENTER , false ) ; <START_BUG> parallelGroup . add ( button , DEFAULT_SIZE , DEFAULT_SIZE , Integer . MAX_VALUE ) ; <END_BUG> parallelGroup . add ( text , PREFERRED_SIZE , DEFAULT_SIZE , PREFERRED_SIZE ) ; groupLayout . setVerticalGroup ( parallelGroup ) ; composite . setLayout ( groupLayout ) ; return composite ; } protected String getCurrentWord ( ) { } @ Override protected void doSetFocus ( ) { } protected abstract void addButton ( Composite composite ) { } protected abstract void addListeners ( ) { } } class WordsWithContentProposalCellEditor extends StringListWithContentProposalsPropertyController . AbstractWordsWithContentProposalCellEditor { private final IValueEditor < String > valueEditor ; public WordsWithContentProposalCellEditor ( Composite parent , String [ ] proposals , String tooltip , IValueEditor < String > valueEditor ) { } @ Override protected void addListeners ( ) { } @ Override protected void addButton ( Composite composite ) { } @ Override protected List < String > doGetValue ( ) { } @ Override protected void doSetValue ( Object val ) { } } }

Fix:
parallelGroup . add ( button , 0 , 0 , Integer . MAX_VALUE ) ;